Mail handling device



1966 M. G. BARNARD ET AL 3,23%,355

MAIL HANDLING DEVICE Filed Dec. 21, 1961 6 Sheets-Sheet 1 1 VENTORS MONROE 6:. HQURRD WALTER S- HANSON wmimmm b.

6 Sheets-Sheet 2 w? mm. 3 E N? Feb. 22, 1966 M. 5. BARNARD ET AL MAIL HANDLING DEVICE Filed Dec. 21. 1961 Fell 1956 M. G. BARNARD ET AL 3,236,355

MAIL HANDLING DEVICE Filed Dec. 21, 1961 6 Sheets-Sheet 5 wan Ramon Y knwfimce m. \IHAHULHK lbwwk HTTORNE Feb. 22, 1966 M. G. BARNARD ET AL 3,236,355

MAIL HANDLING DEVICE 6 Sheets-Sheet 4 Filed Dec. 21, 1961 Feb. 22, 1966 M. e. BARNARD ET AL 3,236,355

MAIL HANDLING DEVICE Filed Dec. 21, 1961 5 Sheets-Sheet 5 \NRLTGR 5. M8010 BY Lnwaeu e M. HRHOLAK UUMZMMW- Feb. 22, 1966 M. G. BARNARD ET AL 3,236,355

MAIL HANDLING DEVICE Filed Dec. 21, 1961 6 Sheets-Sheet 6 INVENTOR. MoNflOE G. Beware!) WHLTGR :3. Hanson BY Lameloce N. \IM HOLAK wmwwwm United States Patent 3,236,355 MAIL HANDLING DEVICE Monroe G. Barnard, Westport, Walter J. Hanson, Gld Greenwich, and Lawrence N. Varholak, Fairiield, Conn., assignors to Pitney-Bowes, Inc., Stamford, Conn., a corporation of Delaware Filed Dec. 21, 1961, Ser. No. 161,117 Claims. (Cl. 198-30) This invention relates to an apparatus for handling pieces of letter mail to orient the latter preparatory to performing operations thereon such as any one or more of facing, stamp cancelling and sorting.

Mail, when picked up and delivered to a post oflice for transmittal is, in large part, non-oriented and includes packages, newspapers and other articles along with letter mail. After culling out all but the letter mail, the latter (which includes post cards as well as filled envelopes) is ordinarily faced (arranged in groups with all of the stamps facing in one direction and located at one corner), cancelled (by overprinting the stamps with a cancellation mark) and sorted (according to class and destination). With the apparatus of the present invention, the nonoriented pieces of letter mail are oriented by causing them to flow in a roughly regulated stream, then declumping the letter mail pieces of this stream, then causing the letter mail pieces to be edged and further streamed by acting upon them to bring one of their longer edges against guide means and accelerating their rate of flow, and then delivering the pieces of letter mail in the proper attitude for stacking or further processing; all this being preparatory to said facing, cancelling and sorting operations.

Accordingly, an object of this invention is to provide a new and improved apparatus useful in handling pieces of letter mail for orienting the same.

Further objects of the invention include providing such an apparatus which incorporates means for causing batches of letter mail to flow in a roughly regulated stream, means for de-clumping the letter mail pieces of this stream and means for causing the de-clumped pieces of the stream to be edged and further streamed.

Another object of the invention is the provision of an improved apparatus for separating and feeding pieces of letter mail in a stream from a reservoir of non-oriented letter mail pieces. Additional objects are to provide such an apparatus which includes de-clumping means and which is relatively jam-free.

Another object is to provide an improvedapparatus for edging and streaming pieces of letter mail. Further objects are to provide such an apparatus which is effective to turn letter mail pieces from edged condition at one of their respective shorter edges to edged condition at one of their longer edges, which is effective to withdraw socalled flats from the stream, and which is effective to deliver a stream of edged pieces of letter mail in the proper attitude for stacking or further processing.

Further objects and advantages will become apparent as the description proceeds.

An embodiment of the invention is shown in the accompanying drawing wherein:

FIG. 1 is a perspective view of a letter handling apparatus according to the invention, this view including an inclined conveyor unit, a chute, a rotary edging and streaming unit, a letter turning unit and a tandem facercanceller unit;

FIG. 2 is a front elevational view of the inclined conveyor unit, the chute and a portion of the rotary edging and streaming unit, certain of the parts being broken away and others being shown in section;

FIG. 3 is a top plan view of a portion of the inclined conveyor unit;

FIGS. 4 and 5 are fragmentary front elevational views of respective portions of the inclined conveyor unit, these views being on respective scales enlarged over that of FIG. 2.

FIG. 6 is a fragmentary front elevational View of a portion of the structure shown in FIG. 5, this view being on a scale enlarged over that of FIG. 5;

FIG. 7 is a fragmentary side elevational view of a portion of the structure shown in FIG. 6;

FIG. 8 is a top plan view of a portion of the inclined conveyor unit, the chute, the rotary edging and streaming unit and the letter turning unit;

FIGS. 9 and 10 are fragmentary sectional views taken along the lines 99 and 10-10, respectively, in FIG. 8;

FIG. 11 is a fragmentary elevational view of a presser member;

FIG. 12 is a fragmentary top plan view of a portion of the rotary edging and streaming unit which includes a fiat-snatcher;

FIG. 13 is a fragmentary elevational View of the structure shown in FIG. 12; and

FIG. 14 is a schematic wiring diagram for the mail handling apparatus.

Referring to FIG. 1, an apparatus embodying the present invention is shown as including an inclined conveyor unit, a chute, a rotary edging and streaming unit, a letter turning unit and a tandem facer-canceller unit generally designated at 20, 22, 24, 26 and 28, respectively. These respective units will be described in the order in which they operate upon the pieces of letter mail to orient the same.

With reference to FIGS. 2-7 along with FIG. 1, the inclined conveyor unit 20 represents an improvement over the feeding unit disclosed in copending US. patent application Serial No. 15,336, filed on March 16, 1960 by F. J. Liberty et al., now Patent No. 3,061,067. The unit 20 includes a frame 30 which supports a guideway having upstanding sides 32, 34 and a flat bottom 36.

The lower end of the guideway takes the form of a hopper 38 for receiving batches of non-oriented pieces of letter mail of mixed widths, lengths and thicknesses.

The frame 30 carries two pairs of bearing members 40. One of these pairs of bearing members 40 rotatably supports a shaft 42 on which an idler roller 44 is mounted at the lower end of the guideway. At the upper end of the guideway the other pair of bearing members 40 rotatably support a shaft 46 on which a driven roller 48 is fixed. An endless belt 50 is entrained about the rollers 44 and 48 with the upper inclined reach 52 of this belt extending through an opening 54 at the bottom of the hopper 38 and along the bottom 36 of the guideway. The outer surface of the belt 50 provides a coefilcient of friction between itself and a piece of letter mail greater than that between two pieces of letter mail. This belt 50 may be ribbed as shown in FIGS. 3 and 4.

The roller 48 and the belt 50 are driven by a motor 56 to drive the belt in the direction from the lower end of the inclined reach 52 toward the upper end thereof. The motor 56 is mounted on a platform 58 supported from the frame 30 by a sub-frame 60. Through a pair of belt-connected pulley wheels 62, 64, the motor 56, when energized, continuously drives the input to a conventional speed reduction unit 66. The output of the speed reduction unit 66 drives a pulley wheel 68 which, through a belt 70, drives a pulley wheel 72. A belt tensioning roller 73 is conventionally arranged to keep the belt 70 under tension. The pulley wheel 72 is fixed to the input of a clutch generally indicated at 74 in FIG. 7. The clutch 74 is of conventional construction being disclosed, for example, in US. Patent No. 2,766,569, granted on October 16, 1956 to J. A. Strother et al. The output of the clutch 74 is fixed to the shaft 46 on which the roller 48 is mounted as best shown in FIG. 7. In wellknown fashion as also disclosed in the above-noted patent to J. A. Strother et al., control over the engagement and disengagement of the clutch 74 is effected by a helically wound brake spring 76. One end of the brake spring 76 is anchored to a pin 78 secured to the frame 30 and the other end is secured to the plunger of a solenoid 80. Normally the solenoid 80 is de-energized so that the brake spring 76 is slack and the clutch 74 is engaged. When the solenoid is energized, the plunger thereof tensions the brake spring 76 and disengages the clutch until the solenoid is de-energized.

' So long as the clutch 74 remains engaged and the motor 56 is-energized, the endless belt 50 is continuously driven about a closed path to move the upper inclined reach 52 thereof in the direction from the lower end of this reach to the upper end thereof. Non-oriented pieces of letter mail deposited inthe hopper 28 will be conveyed by the belt 50 from the hopper in clumps and separate pieces. The initial flow of letter mail pieces from the hopper 38 includes clumps of limited height by virtue of the inclination of the upper reach 52 of the belt 50. Theinclined conveyor unit 20 incorporates several additional features for de-clumping the flow of letter mail pieces as'will now be described.

Disposed in succession along the inclined belt reach 52 are a plurality of plates 82. Each plate 82 extends from one side 32 of the guideway to the other side 34 and has a pair of side walls 84. Each plate 82 is pivoted adjacent its rearward end by means of a pair of pivot pins 86 each of which is carried by one of the sides 32 and 34 and projects through an aperture in the respective side wall 84. Each of the plates 82 is yieldably urged by gravity to a normal pivotal position at which its forward end is spaced from the adjacent friction surface of the inclined belt. This normal pivotal position of each plate 82 is determined by a stop in the form of a chain 88 secured at one end to one of the plate side walls 84 and at its other end to one of the guideway sides 32, '34. Secured, as by cementing, to the underside of each of the plates 82 is a plurality of flexible friction members 90 which extend, at their forward ends, beyond the forward end of the respective plate 82. The forward ends of the friction members 90 carried by each plate 82 terminate adjacent the friction surface of the inclined belt reach 52 at a distance therefrom less than that of the forward end of the friction members'90 secured to the next preceding plate. It follows that the clearance between'the friction surface of the belt 50 and the forward ends of the friction members 90 carried by each successive plate 82 decreases in the direction of mail flow along the inclined belt reach 52. As a consequence, the friction members 90, whichact as wipers, wipe back the uppermost ones of exessively high clumps of mail as thees clumps and parts thereof move along the inclined b elt reach 52, By virtue of the yieldably biased pivotal mounting of the plates 82, jamming of clumps of mail between the plates and the surface of the belt 50 is avoided.

Each plate 82 is formed of a material such as steel whereby the upper surface of each of these plates is an anti-friction surface. Each of the plates 82, in the direction from its forward end to its rearward end, is downwardly inclined and diverges from the friction surface of the inclined belt reach 52. Also, the trailing end of each of the plates 82 is disposed, as shown in each of FIGS. 2, 4 and 5, below and sufliciently near the leading end of the next succeeding plate that any of said pieces of mail that slide off the leading end of any one of the plates 82 fall onto the next preceding plate. As pieces of letter mail are wiped back by the friction members 90, these pieces tend to slide back toward and onto the upper surface of the next preceding plate 82. Once this occurs, such pieces slide off the latter plate onto the next preceding plate and so on back to the hopper 38. It can be seen, then, that the succession of plates 82 along with the friction members act as a nonjamming de-clumping means for the pieces of mail being transported along the inclined belt reach 52.

When the pieces of mail reach substantially the upper end of the inclined belt reach 52, these pieces enter the zone of influence of another de-clumping means generally designated by the reference numeral 92. As can be seen in FIGS. 2, 5, 6 and 9, the de-clumping means 92 includes a plurality of rollers 94 fixed to and mutually spaced along a shaft 96. As many rollers 94 are provided as are necessary to accommodate the width of the inclined conveyor guideway. Each roller 94 is in the form of a steel disc covered at its outer periphery by an annulus 98 of friction material such as rubber. The roller shaft 96 is supported for rotation at one end of two parallel arms 100 each of which is fixed at its opposite end to a rock shaft 102 rockably supported by two brackets plates 104. The bracket plates 104 are supported, in turn, -by the frame 30. A supporting plate 106 is fixed to the upper edges of and extends between the two parallel arms 100. This plate 106 mounts a motor 108 which drives a sprocket wheel 110. A sprocket chain 112 is driven by the sprocket wheel and drives a sprocket wheel 114 fixed on the roller shaft 96. So long as the motor 108 is energized the rollers 94 are driven in the clockwise direction as viewed in each of FIGS. 2, 5 and 6. The linear velocity of the periphery of the rollers 94 is substantially greater than the linear velocity of the endless belt 50.

Adjustably fixed to the rock shaft 102' (as by a set screw) is an arm 116 having a right angle flange 11 8. The weight distribution of all of the parts (including the rollers 94, arms 100 and motor 108) which rock with the rock shaft 102 is such that the center of gravity of these parts remains on the same side of the axis of the shaft 102 as the rollers 94 are located. As :a consequence, the rollers 94 are yieldably urged in the counterclockwise direction (as viewed in FIGS. 2, 5 and 6) toward the friction surface of the belt 50. A block 120 is fixed on one of the brackets 104 and threadedly receives an adjusting screw 122 which is engageable with the flange 118 to limit the extent of movement of the rollers 94 toward the friction surface of the belt 50. The adjusting screw 122 is set to maintain the normal position of the friction surfaces of the rollers 94 at a distance from the friction surface of the belt '50 slightly greater than the average thickness of the pieces of letter mail to be handled.

Two electrical switches 124, 126 are mounted on one of the bracket plates 104 as best shown in FIG. 6. The switch 124 is fixed on the bracket plate 104, and the arm 116 is secured in adjusted position relative to the rock shaft 102 such that the actuating arm 128 of the switch 124 is tripped when the rollers 94 move to a location at a first predetermined distance from the adjacent friction surf-ace of the belt 50 in the direction away from the belt 50. This first predetermined distance is slightly greater than the average thickness of the letter mail pieces to be handled. An adjustable screw 130 is carried by the flange 118 so that its headed end trips the actuating arm 132 of the switch 126 when the rollers 4 move to a location at a second predetermined distance from the adjacent friction surface of the belt 51 this second predetermined distance being equal to the maximum single piece thickness to be handled.

The operation of the de-clumping means 92 will now be described with reference to the wiring diagram of FIG. 14 along with FIGS. 2, 5, 6 and 7. The motor 56 for driving the belt 50, the solenoid 80 which controls the clutch 74, the motor 168 for driving the rollers 94, and the switches 124 and 126, all as previously described, are electrically connected as shown in FIG. 14. Each one of a pair of leads 134, 136 is connected to one side of a line source of electric current. After a main switch 138 is manually closed, the motor 56 is energized providing that a manual switch 140 was previously closed. This closing of the main switch 138 also establishes an electrically conductive path leading from the switch 140, through a normally closed relay contactor 142 and an overload relay 144 to the motor 168 for energizing the latter. Consequently, pieces of letter mail are carried past the de-clumping plates 82 and wiper friction members 90 to the location between the rollers 94 and the belt 50. So long as only single pieces of letter mail of average thickness or slightly greater than average thickness move under the rollers 94, these pieces will be unafiected by the rollers 94 and will drop off the upper end of the inclined belt reach 52 in succession into the chute 22.

When any clump of mail pieces that reaches the rollers 94 has not been reduced to a height less than the distance between the belt 58 and the rollers 94 when the latter are in their normal position, the rollers 94 will yield upwardly about the rock shaft 1il2. It will be recognized, of course, that the clump height will be somewhat reduced due to the downward yieldable urging of the rollers 94. So long as such a clump is of a height less than the predetermined distance between the belt and rollers 94 at the point when the switch 124 closes, the belt 50 and the rollers 94 continue to run and the rollers 94 operate to impel, in succession, the uppermost ones of the clump beyond the remaining piece or pieces of the clump.

When the height of a clump is sutficiently great to cause the rollers 94 to yield upwardly to the extent that the switch 124 to tripped but this clump height is not greater than the maximum single piece thickness to be handled, the drive to the belt 51 is stopped. Referring to FIG. 14, when the switch 124 closes, an electrically conductive path is established through the switch 124, a normally closed relay contactor 146 and the solenoid 80 to energize the latter. gagement of the clutch 74 to stop the drive to the belt 50. The belt 50 remains stopped as the rollers 94 continue to impel successive uppermost pieces of the respective clump forwardly until the clump is reduced to a height such that the switch 124 re-opens. This causes the solenoid to be de-energized, the clutch 74 re-engages and the belt 59 starts to be driven again about its closed path.

If a single piece of mail moves under the rollers 94 which is sufiiciently thick that the switch 124 is closed but which is less than the maximum single piece thickness to be handled, the solenoid 80 will be energized, as before, to stop the belt 50. This creates an excessive drag on the motor 168 because, in this situation, both the stopped belt 50 and the driven rollers 94 are in frictional contact with the single piece. As a result, the motor 1138 draws an excessive current which causes the overload relay 144 to pick up. As shown in FIG. 14, the closing of the contactor 148 of the overload relay 144 establishes an electrically conductive path through a relay 158 causing the latter to pick-up. The contactor 146 of the relay 150 opens to break the electrically conductive path from the switch 124 through the relay contactor 146 to the solenoid 89 with the result that the solenoid 80 is de-energized, the clutch '74 is re-engaged and the drive to the belt 50 is re-started. Since the rollers 94 Energization of the solenoid 80 elfects dis-enare driven at a peripheral velocity greater than the linear velocity of the belt 50, the drag on the motor 108 remains sulficiently high that the overload relay remains in the picked up condition. When this single piece is driven out from between the belt 50 and the rollers 94, this drag on the motor 108 ceases, the overload relay 144 drops out, the contactor 148 re-opens, the relay 15E) drops out and the contactor 146 closes, but at the same time the switch 124 re-opens so that the solenoid remains deenergized and the drive to the belt 50 continues. It follows that the drive to the belt 50, once it re-starts, continues until the single piece is fed from between the rollers 94 and belt 59 and thereafter so long as no new condition develops to cause the drive to this belt to be stopped. It will be apparent that the overload relay 144 does not pick up when a clump of several pieces of mail of a total height equal to said single piece enter between the rollers 94 and belt 50 for the reason that the coeflicient of friction between two pieces of letter mail is substantially less than the respective coefiicient of friction between a piece of letter mail and each one of the surface of the belt 58 and the surface of the rollers 94.

In the manner described above, the overload relay 144 acts as a variable time delay relay responsive to a single piece of mail between the belt 50 and rollers 94 that is of sufiicient thickness to cause closing of the switch 124 but of less than the maximum single piece thickness to be handled. This relay responds to start up the drive to the stopped belt and to continue this drive for a variable length of time even though the switch 124 remains closed; this length of time being that required to drive the single piece out from between the belt 50 and rollers 94. Of course, a conventional time delay relay could be provided which is responsive in the same manner as the relay 144 but for a fixed length of time sufiicient to drive out from between the belt 50 and rollers 94 the longest single piece of letter mail to be handled. This would have the advantage of requiring a less sensitive relay (since it would not have to sense the reduced drag on the motor 108 after the drive to the belt 51} re-started), but would have the disadvantage that the drive to the belt 50 would not be stopped as quickly if a very short single piece of less than said maximum single piece thickness were to cause tripping of the switch 124 and was immediately followed by a clump of pieces whose combined height was also less than said maximum single piece thickness but sufficient to cause tripping of the switch 124.

When a single piece of letter mail reaches the rollers 94 that is of a thickness greater than the normal space between the rollers 94 and the belt 59 but less than the thickness which would cause the switch 124 to close, the drive to the rollers 94 and belt 50 is not interrupted and the single piece is fed into the chute 22. In this situation, the overload relay 144 will pick up causing the relay 150 to open the contactor 146, but since the switch 124 (as well as the relay contactor 154) is open, the effect is to open an already open current path to the solenoid 80 so that the latter remains de-energized and the drive to the belt 50 (and to the roller 94) continues.

When a single piece of letter mail enters between the belt 50 and the rollers 94 that is of greater thickness than the maximum to be handled, both the drive to the belt 50 and the drive to the rollers 94 are stopped. Referring to FIG. 14 in this regard, this condition causes the switch 126 to be closed along with closing of the switch 124. The switch 126 being in series with a relay 152, the latter picks up to close two relay contactors 154 and 156 and to open the relay contactor 142. The closing of the contactor 156 establishes an electrically conductive hold-in path leading from the switch through the contactor 156, a manual reset switch 158 and the relay 152 to keep the latter energized even though the switch 126 is subsequently re-opened. The opening of the contactor 142 when the relay 152 picks up causes the motor 108 to be de-energized whereby the drive to the roller 94 stops.

Necessarily the overload relay 144 will not be picked-up since opening of the contactor 142 also de-energizes this relay. The closing of the contactor 154 establishes an electrically conductive path through the contactor 154 and the contactor 146 of the relay 150 to the solenoid 80. As a consequence, the solenoid 80 is energized to disengage the clutch 74 and stop the drive to the belt 50. It will be clear that the switch 140, as well as each of two other switches 162 and 164, will ordinarily be manually closed before the main switch 138 is closed.

It will be apparent from the above, then, that the entry between the belt 50 and rollers 94 of a single piece of mail of a thickness greater than the maximum to be handled causes the relay 152 to pick-up whereupon the drive to the belt 50 and the drive to the rollers 94 are stopped. An operator can then remove the offending piece of mail from between the belt 50 and rollers 94. After this is done, operation of the inclined conveyor unit 20 starts again when the reset switch 158 is manually opened momentarily. This breaks the abovedescribed hold-in current flow path through the contactor 156, the switch 158 and the relay 152 whereupon the latter is de-energized, the motor 108 is energized and the clutch 74 is re-engaged.

Of course, if a clump of pieces of letter mail greater in total thickness than said maximum single piece thickness should enter between the belt 50 and the rollers 94, the drive to the belt 50 and to the rollers 94 would stop. This is an unlikely prospect and rarely, if ever, occurs due to the tie-clumping action of the inclined belt reach 52 (since only a limited number of pieces can be picked up in a clump and ride any substantial distance before sliding back toward the hopper) and due also to the de-clumping action of the plates 82 and wiping friction members 90. If this should occur, however, the operator need only remove the clump from between the belt 50 and the rollers -94 and then momentarily open the manual reset switch 158.

Briefly to reiterate the operation of the de-clumping means 92, a single piece of letter mail whose thickness is less than, equal to or slightly greater than the average thickness, is not affected by the rollers 94 since the peripheral surface thereof is normally spaced from the adjacent portion of the friction surface of the belt 50 a distance slightly greater than said average thickness. When the height of a clump of mail consisting of two or more letter mail pieces is greater than the normal spacing between the rollers 94 and the belt 50 but less than the predetermined thickness which would cause the switch 124 to be tripped (due to the rollers 94 yielding upwardly about the rock shaft 102), the rollers 94 operate to impel, in succession, the uppermost ones of the dump beyond the remaining piece or pieces of the clump. When the height of a clump is greater than said predetermined thickness but less than the maximum single piece thickness to be handled, the drive to the belt 50 stops until the rollers 94 reduce the height of the clump (by impelling the uppermost pieces thereof forwardly of the remainder of the clump) to an amount less than said predetermined thickness whereupon the belt drive starts again. If the thickness of a single piece of letter mail is greater than the normal space between'the rollers 94 and belt 50 but less than said predetermined thickness, the rollers 94 and belt 50 will feed the single piece out from therebetween without interruption in the drive to the rollers 94 or to the belt 50. If the thickness of a single piece of letter mail is greater than said predetermined thickness but less than the maximum single piece thickness, the drive to the belt 50 stops but then re-starts and continues thereafter until the respective single piece drops into the chute 22 and a clump or a single piece greater than said predetermined thickness subsequently enters between the rollers 94 and belt 50. If a single piece of letter mail having a thickness greater than the maximum single piece thickness to be handled enters between the rollers 94 and belt 50, the

8 drive to both the rollers 94 and to the belt 50 stops and remains so until the piece is removed and the reset switch 158 is manually opened. This same operation will occur if a clump having a height greater than said maximum single piece thickness reaches the rollers 94, but this rarely occurs as previously noted.

It will be clear that the de-clumping means 92 operates with no wear, friction or contact between the surfaces of the rollers 94 and belt 50 since the two are always spaced apart at least the amount that is the case when the rollers 94 are in their normal position.

Pieces of letter mail are driven off the upper end of the inclined belt reach 52 in a regulated stream by the inclined conveyor unit 20 as described above. The successive pieces drop into a chute 22 from the inclined conveyor unit 20. As shown in FIGS. 1 and 8, the upstanding sides 32, 34 of the guideway of the unit 20 are forwardly extended to form respective portions of the chute 22. The extension of the guideway side 32 stands substantially vertically, the extension 172 of the guideway 34 is integral with a downwardly and inwardly inclined section 174 which joins, as does the vertical extension 170, one side of a downwardly and forwardly inclined bottom chute section 176. As can be seen in FIGS. 5 and 8, a forwardly and downwardly inclined section 178 extends between the extensions 170 and 172, and connects with a forwardly and more steeply downwardly inclined section 180. The section 180 extends between the section 174 and the extension 170, and also joins with the bottom chute section 176. The successive pieces of letter mail, after they fall into and slide along the chute 22, tend to arrive at the discharge end of this chute with one of their shorter edges foremost; this being due, in part, to the transverse dimension of the bottom chute section 176 which is greater than the width but smaller than the length of most pieces of letter mail.

Under the impetus of sliding down the chute 22, the successive pieces of letter mail move onto the upper surface of an annular disc 182 of the rotary edging and streaming unit 24. This unit 24 represents an improvement over the rotary edging and streaming unit disclosed in the above-cited US patent application Serial No. 15,336. The annular disc 182 is supported for rotation about a vertical axis and in the clockwise direction as viewed in FIG. 8 by three substantially equally spaced rollers 184. Each of the rollers, as shown in FIG. 10, is supported for free rotation about a horizontal axis by a yoke bracket 186 fixed to the upper surface of a circular supporting table 188. The table 188 is supported, in turn, by a plurality of legs 190, one of which can be seen in FIG. 2.

Stability of the annular disc 182 against horizontal shifting is effected by three rollers 192, 194 and 195 (FIG. 8). The annular disc 182 is fixed to or integral with a pair of downwardly extending rigidifying flanges 198 and 200, respectively, and each of the rollers 192, 194 and 196 bears against the radially inner surface of the flange 200 to provide this horizontal stability. The annular disc 182 is rotatably driven by the roller 192. As shown in FIG. 10, the roller 192 is fixed to a shaft 202 supported for rotation by a bearing bracket 204, The bearing bracket 204 is mounted on the table 188 directly over an aperture 206 in the table. The shaft 202 extends through the aperture 206 and fixedly carries a sprocket wheel 208 at its lower end. A sprocket chain 210 meshes with the sprocket wheel 208 and with another sprocket wheel 212 fixedly carried by the shaft of a motor 214 (FIG. 8). The motor 214 is supported by the table 188 and, when energized, rotatably drives the annular disc 182 through the sprocket chain 210 and roller 192. The rollers 194 and 196 are supported in a manner similar to that of the driving roller 192 except that each of the rollers 194 and 196 is a freely rotatable idler roller rather than being a driving roller.

The upper surface of the annular disc 182 is formed by 9 an annular strip 216 of friction material such as rubber whereby the coefiicient of friction between the upper surface of the annular disc and a piece of letter mail is greater than that between two pieces of letter mail.

Disposed about a substantial portion of the periphery of the annular disc 182 is an upstanding arcuate guide 218. The arcuate guide 218 is formed of a plurality of tandem sections and is secured along its length to the outer periphery of the table 188. As pieces of letter mail move onto the upper surface of the annular disc 182 from the chute 22, these pieces are moved by the disc 182 in the direction of rotation thereof and are urged by centrifugal force against the arcuate guide 218. Being so urged, against the guide 218, these letter mail pieces are edge that is, one of the respective edges of each of the pieces moves into engaging registration with the arcuate guide. The speed of rotation of the annular disc 182 is sufli'cient that the letter mail pieces slip or lag relative to the disc throughout all or at least a substantial portion of the arcuate path followed by these pieces. Since the coefiioient of friction between two pieces of letter mail is less than that between the friction surface of the annular disc 182 and a piece of letter mail, the tendency is for the lowermost one of two or more overlapping pieces to be driven out from under and forwardly of the remaining piece or pieces. In this manner, not only is additional edging of the letter mail pieces accomplished but so also is additional streaming effected. It will be understood by those skilled in the art that the term streamin refers to separating, in the direction from lead edge to lead edge, articles being fed along a feed path.

As previously noted, most of the letter mail pieces leave the chute 22 with one of their respective shorter edges foremost due, in part, to the bottom chute section 176 being of a width greater than the width of most pieces of letter mail but smaller than the length of these pieces. Another feature that aids in effecting this result lies in the provision of a cut-out 219 (FIG. 8) at the discharge end of the bottom chute section 176. This cutout 219 has little or no effect on a piece of letter mail which moves therepast with one of its shorter edges foremost. When, however, a piece of letter mail approaches the location of the cut-out 219 with one of its longer edges foremost, the tendency is for one of the respective shorter edges thereof to ride against the chute section 174 in elevated location relative to the other shorter edge of that piece; this other shorter edge ordinarily riding at or close to the junction of the side Wall 178 and the bottom chute section 176. As a consequence this latter shorter edge rides onto the upper surface of the annular disc 182 at the location below the cut-out 219 while the elevated shorter edge thereof is in engagement with the chute section 174. The tendency is for the shorter edge engaging the upper surface of the annular disc to be driven forwardly of the elevated shorter edge whereby the piece of letter mail is turned to bring the driven shorter edge foremost. Occasionally, however, one of the letter mail pieces will have one of its shorter edges register with the guide 218 as shown, for example, at L in FIG. 8. The manner in which this condition is accommodated by the unit 24 will now be described.

A presser member 220 is provided which includes a hub 222 supporting a circular brush 224 formed of flexible bristles which extend radially outward from the hub 222 (see FIGS. 8 and 11). The hub 222 along with the brush 224 is rotatable freely about one end of a crank arm 22 6. The opposite end of the crank arm 226 is retained for free rotation by a bearing block 228 mounted on a circular cover plate 23%) later to be described in detail. As shown in FIG. ll, the presser member 226 can be set in adjusted position transversely of the upper surface of the annular disc 182 by loosely inserting the end of a set screw 232 in a selected one of a plurality of grooves 234 in the crank arm 226. By setting the presser member 220 in a transverse position such that it lies a distance from the guide 218 slightly greater than the maximum width of the letter mail pieces to be handled (this will be less than the length of the shortest pieces to be handled), a letter mail piece in the attitude of the letter L in FIG. 8 will be swung or turned in a horizontal plane to bring its leading longer edge into edged condition against the guide 218. In this regard, the presser member 220 acts in the same manner as its counterpart in said copending US. patent application Serial No. 15,336 in the respect that under the weight of its parts, the presser member urges each piece of letter mail passing thereunder into firmer driven engagement with the annular disc. Since each piece of letter mail slips or lags behind the annular disc, the effect of the downward urging of the presser member is to cause the annular disc to drive the portion of the letter mail piece pressed thereagainst, ahead and about the leading corner of that piece at the guide 218. The resulting counterclockwise turning (as viewed in FIG. 8) of the letter mail piece brings the leading longer edge of the piece into edged condition against the guide 213; all this as the piece continues to move along the arcuate path defined by the guide 218.

The previously mentioned cover plate 230 extends along a substantial portion of the length of the arcuate path followed by the pieces of letter mail as they move into edged condition against the arcuate guide 218. The cover plate 236 provides a cut-out portion 235 to accommodate radial adjustment of the presser member 226. The cover plate 230 is preferably formed in separately connected sections and is preceded by a cover plate 236 attached to the arcuate guide 218 in the same manner as the cover plate 239. The lead-in end of the cover plate 236 is formed with an inclined portion 238 which acts to deflect pieces of letter mail toward the annular disc 132 from the chute 22.

When the annular disc 182 rotates, the air directly thereabove tends to be urged radially outwardly by centrifugal force just as are the pieces of letter mail. Since the cover plates 230, 236 extend radially inwardly from the guide 218, the air directly above the annular disc 182 is substantially confined by the guide 218 and the cover members 230, 236 against radially outward movement. As a consequence, the air directly above the annular disc 182 is substantially confined for movement in the direction of movement of the annular disc. This acts to decrease the planing" effect of letter mail pieces. In this regard, the pieces of letter mail, particularly those with an upwardly bent leading end, tend to lift off the friction surface of the annular disc as they move past the air thereabove. With this air moving in the same direction as the letter mail pieces, however, this tendency is decreased.

Another presser member 240 is provided as shown in FIGS. 8 and 9. The presser member 240 takes the form of a flap formed of a flexible material such as rubber. The flap 240 is supported by a bracket 242 secured to the cover plate 234). The flap 240 extends from the bracket 242 through a space between the cover plates 230, 236 into converging relation with the upper surface of the annular disc 182 in the direction of movement of the latter. The presser member 240 acts, as do its counterpart presser members in the above-cited US. patent application Serial No. 15,336, to urge the successive pieces of letter mail into firmer engagement with the disc 182 thereby to increase the edging and streaming efiiciency of the unit 24.

It sometimes occurs that so-called flats or oversize pieces of letter mail such as that shown at L" in FIG. 8 are delivered by the unit 20 and chute 22 to the unit 24. Such pieces are greater in width than the maximum to be handled, and a flat-snatcher generally designated at 244 in FIGS. 8, l2 and 13 is provided to discharge such pieces 11 from the system automatically. The flat-snatcher 244 includes a series of three driven rollers 246, 248 and 250, each of which is similarly fixed on a responsive shaft 252 rotatably mounted in a respective bearing block 254 secured to the table 188. An enlarged diameter portion of the shaft 252 on which the roller 246 is fixed, is driven through a universal joint 256, a drive shaft 258, a universal joint 260, a shaft 262, and a pair of pulley wheels 266, 268 about which an endless belt 270 is entrained; the pulley wheel 268 is being driven by an electric motor 272. The shaft 262 is rotatably supported by a bearing block 274. The bearing block 274 and the motor 272 are supported by respective brackets (not shown) which are carried by the table 188.

As best shown in FIGS. 12 and 13, a pulley wheel 276 is fixed on the shaft 252 mounting the roller 246, a pair of pulley wheels 278 and 280 is fixed on the shaft 252 mounting the roller 248, and a pulley wheel 282 is fixed on the shaft 252 mounting the roller 250. An endless belt 284 drives the pulley wheel 278 from the pulley wheel 280 and an endless belt 286 drives the pulley wheel 282 from the pulley wheel 280. Each one of three idler rollers 288, 290 and 292 opposes and is resiliently biased toward a respective one of the three driven rollers 246, 248 and 250. In this regard, each one of the idler rollers 288, 290 and 292 is rotatably supported by a yoke member 294 which is resiliently biased downwardly by a torsion spring 296 in conventional fashion about a pivot pin 298 secured to a contoured plate 380. The plate 300 is carried by a bracket 301 mounted on the table 188.

Each pair of rollers 246 and 288, 248 and 290, and 250 and 292, diverges, as best shown in FIGS. 8 and 12, at an angle from the feed path of pieces of letter mail on the annular disc greater than that at which the respectively preceding one of these pairs of rollers diverges. Also, the bite between the pair of rollers246, 288 is disposed radially inwardly of the annular disc 182. This roller bite will be located at a distance from the arcuate guide 218 slightly greater than the maximum width of letter mail pieces to be handled. As a consequence, a so-called flat which is being impositively driven by the annular disc 182 will enter the bite between the rollers 246, 288 and-will be positively withdrawn thereby from the annular disc and into the bite between the rollers 248, 290. From the rollers 248, 290, the flat will be directed into the bite between the roller pair 250, 292 from which the flat will be directed under a hood 302 provided by a cover plate 304, against a deflector 306, and downwardly through an opening 308 in the table 188. To aid in directing the lead edge of each flat into the bite between the rollers 248, 290, an arm 310 is provided that is carried in cantilever fashion by the pivot pin 298 about which the roller 288 pivots. A pair of idler rollers 312 carried by the arm 310 act as an anti-friction means for downwardly deflecting the leading edges of the flats as the latter approach the rollers 248, 290. A container (not shown) may be placed under the table 188 in position to receive the flats withdrawn from the annular disc.

As can best be seen in FIG. 8, the arcuate guide 218 diverges away from the periphery of the annular disc 182 from a point adjacent the fiat-snatcher 244 to the discharge end of the arcuate guide. A horizontal, curved plate 314 is supported by the table 188 at a level just below the annular disc. The plate 314 extends radially outwardly from under the annular disc to the arcuate guide 218.

The successive pieces of letter mail slide off the annular disc 182 onto the plate 314 while remaining in edged condition against the arcuate guide 218. The cover member 230 terminates short of the discharge end of the plate 314 and supports adjacent its end a flexible finger 316 similar to the flap 248 in FIG. 9. The finger 316 urges each successive piece of letter mail downward- 12 ly against the plate 314 as the successive pieces move off the plate 314.

From the rotary edging and streaming unit 24, the pieces of letter mail can be directed to a horizontal stacker as disclosed in said U.S. patent application Serial No. 15,336. Alternatively, the successive pieces can be directed through a letter turning unit 26 to a tandem facer canceller unit 28. Such a tandem facer canceller unit is disclosed, for example, in U.S. Patent No. 2,947,406 granted on August 2, 1960 to H. S. Hazelton, J r.

The letter turning unit 26 is similar to the one depicted in said U.S. patent to H. S. Hazelton, Jr. in that the former turns each successive piece of letter mail about a horizontal axis whereas the latter turns the pieces The letter turning unit 26 includes two endless belts 318, 320. The belt 318 is entrained about two rollers 322 and 324, and the belt 320 is entrained about two rollers 326 and 328. The rollers 322, 324, 326 and 328 are ositioned so that the two inner reaches of the belts are in face-to-face engagement with each other. As can be seen in FIG. 8, the rollers 322, 326 are mounted for rotation about vertical axes and the rollers 324 and 328 are mounted for rotation about horizontal axes whereby the face-to-face engagement of said inner reaches of the belts 318, 320 gradually changes from horizontal at the input of the unit 26 to vertical at the output thereof. The belts 318 and 320 are driven in the respective directions to move the inner reaches thereof in the direction from the input to the output (right-to-left in FIG. 8) of the unit 26. As can be seen in FIG. 8, the roller 328 is mounted for rotation about a horizontal axis canted slightly from parallelism with the rotational axis of the roller 324. This provides a tendency for the belt 320 to be urged in the direction of the deflector 238 but the effect is to balance and thereby overcome an inherent tendency for lateral shifting of the mutually engaging surfaces of the belts 318 and 320. The belts 318 and 320 are driven by a motor 330 which, through a pulley wheel 332, drives a belt 334. The belt 334 drives a pulley wheel fixed to the shaft which mounts the roller 326 thereby to drive the belt 318. The belt 334 also drives a pulley wheel fixed on a shaft which also mounts a roller 336. A twist belt 338 is driven by the roller 336 and drives a roller 340. The roller 340, being mounted on the same shaft as the roller 324, drives the belt 320.

Each successive piece of letter mail moves off the discharge end of the edging and streaming unit 24 into the bite between the belts 318, 320 and is turned from a horizontal to a vertical attitude for discharge into the tandem facer-canceller 28 where the pieces are faced and the stamps thereon are cancelled.

The motor 214 for driving the rollers 94, the motor 272 for driving the annular disc 182 and the motor 330 for driving the letter turning belts 318, 320 are electrically connected as shown in FIG. 14. Ordinarily, the switch 140, 162 and 164 will be closed prior to closing of the main switch 138 to begin operation of the mail handling apparatus. A normally open, manually operable stop switch 342 is disposed in parallel relation with the switch 126 and operates, when momentarily closed, in the same manner as that when the switch 126 is closed. That is, the relay 152 is energized and the relay contactor 154 is closed to energize the solenoid 80 to stop the drive to the endless belt 50, the relay contactor 142 is opened to de-energize the motor 108 which drives the rollers 94, and the relay contactor 156 is closed to provide a hold-in circuit for maintaining the relay 152 in energized condition. In this manner the feeding of letter mail pieces to the chute 22 is stopped and remains so until the manual reset switch 158 is momentarily opened.

Since many changes can be made in the embodiment of the invention as particularly described and shown herein without departing from the scope of the invention, it is intended that this embodiment be considered as exemplary 13 and that the invention not be limited except as warranted by the following claims.

What is claimed is:

1. An apparatus for handling pieces of letter mail comprising:

(a) an endless belt providing a friction surface;

(b) means operatively connected for driving said belt about a closed path to transport pieces of letter mail on said friction surface past the forward end of a reach of said belt;

(c) a roller providing a peripheral friction surface;

(d) means mounting said roller at a normal position adjacent said forward end of said reach of said belt;

(e) said roller, in said normal position, being disposed with said peripheral friction surface thereof spaced from the friction surface of said belt a distance slightly greater than the average thickness of the pieces of letter mail to be handled;

(f) means for rotatably driving said roller to move the friction surface thereof adjacent said belt in the same direction as, and at a linear speed greater than, that of the adjacent portion of the friction surface of said belt;

(g) sensing means for detecting the total thickness of the pieces of mail as the latter approach said forward end of said belt reach;

(h) a first control means for stopping the drive to said belt when said total thickness exceeds a predetermined amount and for re-starting the drive to said belt after said total thickness is reduced to said predetermined amount;

(i) and a second control means for re-starting the drive to said belt, after stopping of the drive thereto under the action of said first control, in response to the increased load encountered by said roller when a single piece of mail is disposed between said roller and the stopped belt.

2. An apparatus as set forth in claim 1 and further including a third control means for stopping the drive to said belt and the drive to said roller when said total thickness exceeds a predetermined amount greater than said first-named predetermined amount.

3. An apparatus as set forth in claim 1 including (a) means mounting said roller for movement from said normal position in a direction away from said belt;

(b) said roller being yieldably biased toward said belt;

and

(c) said sensing means for detecting said total thickness comprising a mechanism for sensing the distance of said roller from said belt.

4. An apparatus for handling pieces of letter mail comprising:

(a) an endless belt providing a friction surface and having a reach thereof inclined from a lower end to an upper end;

(b) means operatively connected for driving said belt to move said friction surface in the direction from said lower end to said upper end of said inclined belt reach, to transport pieces of mail on said friction surface in said direction past said upper end of said belt reach;

() means for de-clumping said pieces of mail;

(d) said last-named means comprising a plurality of plates disposed in succession along said inclined belt reach;

(e) a friction member carried by each of said plates to extend forwardly thereof in the direction of belt movement;

(f) each of said plates, in the direction from its forward end to its rearward end, being downwardly inclined and diverging from said friction surface of the inclined belt reach with the forward end of the respective friction member carried thereby terminating adjacent said friction surface of the inclined belt reach at a distance therefrom less than that of the forward end of the friction member carried by the immediately adjacent downstream plate;

(g) whereby clumps of said pieces of mail tend to be spread along the length of the friction surface of said inclined belt reach while being transported.

5. An apparatus as set forth in claim 4 wherein (a) the upper surface of each of said plates is formed of an anti-friction material whereby any pieces of mail urged onto said upper surface of one of said plates slide rearwardly Off the rearward end of the respective plate;

(b) the forward end of each of said plates being disposed below and sufficiently near the rearward end of the immediately adjacent upstream plate that any of said pieces of mail which slide off the rearward end of one of the respective plates in turn fall onto the next preceding plate.

6. An apparatus as set forth in claim 4 (a) including means mounting each of said plates for pivotal movement about an axis adjacent the rearward end of the respective plate;

(b) each of said axes lying parallel to said inclined belt reach and perpendicular to said direction;

(c) each of said plates being yieldably biased in the direction to urge the forward end thereof toward said friction surface;

(d) and stop means operatively associated with each of said plates for defining said distance from said friction surface of the forward end of each respective one of said friction members.

7. An apparatus for handling pieces of letter mail comprising an endless belt providing a friction surface;

means operatively connected for driving said belt about a closed path to transport pieces of letter mail on said friction surface past the forward end of a reach of said belt;

a member providing a peripheral friction surface;

means mounting said member adjacent said forward end of said reach of said belt;

said element being disposed with said peripheral friction surface thereof spaced from the friction surface of said belt a predetermined distance;

means for driving said member to move the friction surface thereof adjacent said belt in the same direction as, and at a linear speed greater than, that of the adjacent portion of the friction surface of said belt;

control means for stopping the drive to said belt if the thickness of a clump of several pieces of mail carried by said belt past said member exceeds said predetermined distance by not more than a given amount, said control means being effective to restart and continue said drive to said belt if a single piece of mail of said thickness is carried by said belt past said rotatable member.

8. The apparatus according to claim 7, wherein:

said control means is further eifective to stop the drive to both said belt and said member if either a single piece of mail or a clump of several pieces of mail, of a thickness greater than said predetermined distance plus said given amount, is carried by said belt past said member.

9. The apparatus according to claim 8, including:

means mounting said member for movment from said normal position in a direction away from said belt;

said member being movable away from said belt in response to movement vtherepast of individual or clumped mail pieces of a thickness greater than said predetermined distance;

said control means being controlled by the distance of said element from said belt.

10. The apparatus according to claim 7, including: means mounting said member for movement from said normal position in a direction away from said belt; said member being movable away from said belt in re- 15 sponse to movement therepast of individual or clumped mail pieces of a thickness greater than said predetermined distance; said control means being controlled by the distance of said element from said belt.

References Cited by the Examiner UNITED STATES PATENTS Snyder 209-82 Aller 209-83 Pike et a1. 19830 Makrides 198-31.1

Stovall 19830 Liberty et a1. 198--3O SAMUEL F. COLEMAN, Primary Examiner.

WILLIAM B. LABORDE, Examiner. 

1. AN APPARATUS FOR HANDLING PIECES OF LETTER MAIL COMPRISING: (A) AN ENDLESS BELT PROVIDING A FRICTION SURFACE; (B) MEANS OPERATIVELY CONNECTED FOR DRIVING SAID BELT ABOUT A CLOSED PATH TO TRANSPORT PIECES OF LETTER MAIL ON SAID FRICTION SURFACE PAST THE FORWARD END OF A REACH OF SAID BELT; (C) A ROLLER PROVIDING A PERIPHERAL FRICTION SURFACE; (D) MEANS MOUNTING SAID ROLLER AT A NORMALLY POSITION ADJACENT SAID FORWARD END OF SAID REACH OF SAID BELT; (E) SAID ROLLER, IN SAID NORMAL POSITION, BEING DISPOSED WITH SAID PERIPHERAL FRICTION SURFACE THEREOF SPACED FROM THE FRICTION SURFACE OF SAID BELT A DISTANCE SLIGHTLY GREATER THAN THE AVERAGE THICKNESS OF THE PIECES OF LETTER MAIL TO BE HANDLED; (F) MEANS FOR ROTATABLY DRIVING SAID ROLLER TO MOVE THE FRICTION SURFACE THEREOF ADJACENT SAID BELT IN THE SAME DIRECTION AS, AND AT A LINEAR SPEED GREATER THAN, THAT OF THE ADJACENT PORTION OF THE FRICTION SURFACE OF SAID BELT; (G) SENSING MEANS FOR DETECTING THE TOTAL THICKNESS OF THE PIECES OF MAIL AS THE LATTER APPROACH SAID FORWARD END OF SAID BELT REACH; (H) A FIRST CONTROL MEANS FOR STOPPING THE DRIVE TO SAID BELT WHEN SAID TOTAL THICKNESS EXCEEDS A PREDETERMINED AMOUNT AND FOR RE-STARTING THE DRIVE TO SAID BELT AFTER SAID TOTAL THICKNESS IS REDUCED TO SAID PREDETERMINED AMOUNT; (I) AND A SECOND CONTROL MEANS FOR RE-STARTING THE DRIVE TO SAID BELT, AFTER STOPPING OF THE DRIVE THERETO UNDER THE ACTION OF SAID FIRST CONTROL, IN RESPONSE TO THE INCREASED LOAD ENCOUNTERED BY SAID ROLLER WHEN A SINGLE PIECE OF MAIL IS DISPOSED BETWEEN SAID ROLLER AND THE STOPPED BELT. 